slsmg.c

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	     tmp = SL_Screen[r2].old;
	     for (j = r2; j > r1; j--)
	       {
		  SL_Screen[j].old = SL_Screen[j - 1].old;
		  SL_Screen[j].old_hash = SL_Screen[j - 1].old_hash;
	       }
	     SL_Screen[r1].old = tmp;
	     blank_line (SL_Screen[r1].old, Screen_Cols, ' ');
	     SL_Screen[r1].old_hash = Blank_Hash;
	     r1++;
	  }
	This_Color = color;
     }
   if (did_scroll) return;

   /* Try other direction */

   for (i = rmin; i < rmax; i++)
     {
	hash = SL_Screen[i].new_hash;
	if (hash == Blank_Hash) continue;
	if (hash == SL_Screen[i].old_hash) continue;

	/* find a match further down screen */
	for (j = i + 1; j <= rmax; j++)
	  {
	     if (hash == SL_Screen[j].old_hash) break;
	  }
	if (j > rmax) continue;

	r1 = i;			       /* beg scroll region */
	di = j - i;		       /* number of lines to scroll */
	j++;			       /* since we know this is a match */

	/* find end of scroll region */
	ignore = 0;
	while ((j <= rmax) && (SL_Screen[j].old_hash == SL_Screen[j - di].new_hash))
	  {
	     if (SL_Screen[j].old_hash == Blank_Hash) ignore++;
	     j++;
	  }
	r2 = j - 1;		       /* end of scroll region */

	/* If this scroll only scrolls this line into place, don't do it.
	 */
	if ((di > 1) && (r1 + di + ignore == r2)) continue;

	/* If there is anything in the scrolling region that is ok, abort the
	 * scroll.
	 */

	for (j = r1; j <= r2; j++)
	  {
	     if ((SL_Screen[j].old_hash != Blank_Hash)
		 && (SL_Screen[j].old_hash == SL_Screen[j].new_hash))
	       {
		  if ((j - di < r1) || (SL_Screen[j].old_hash != SL_Screen[j - di].new_hash))
		    break;
	       }

	  }
	if (j <= r2) continue;

	color = This_Color;  This_Color = 0;
	SLtt_normal_video ();
	SLtt_set_scroll_region (r1, r2);
	SLtt_goto_rc (0, 0);	       /* relative to scroll region */
	SLtt_delete_nlines (di);
	SLtt_reset_scroll_region ();
	/* Now we have a hole in the screen.  Make the virtual screen look
	 * like it.
	 */
	for (j = r1; j <= r2; j++) SL_Screen[j].flags = TOUCHED;

	while (di--)
	  {
	     tmp = SL_Screen[r1].old;
	     for (j = r1; j < r2; j++)
	       {
		  SL_Screen[j].old = SL_Screen[j + 1].old;
		  SL_Screen[j].old_hash = SL_Screen[j + 1].old_hash;
	       }
	     SL_Screen[r2].old = tmp;
	     blank_line (SL_Screen[r2].old, Screen_Cols, ' ');
	     SL_Screen[r2].old_hash = Blank_Hash;
	     r2--;
	  }
	This_Color = color;
     }
}

#endif   /* NOT pc_system */



static int Smg_Inited;

void SLsmg_refresh (void)
{
   int i;

   if (Smg_Inited == 0) return;
#ifndef pc_system
   for (i = 0; i < Screen_Rows; i++)
     {
	if (SL_Screen[i].flags == 0) continue;
	SL_Screen[i].new_hash = compute_hash (SL_Screen[i].neew, Screen_Cols);
     }
#endif

   if (Cls_Flag)
     {
	SLtt_normal_video ();  SLtt_cls ();
     }
#ifndef pc_system
   else if (SLtt_Term_Cannot_Scroll == 0) try_scroll ();
#endif

   for (i = 0; i < Screen_Rows; i++)
     {
	int trashed;

	if (SL_Screen[i].flags == 0) continue;

	if (SL_Screen[i].flags & TRASHED)
	  {
	     SLtt_goto_rc (i, -1); /* Force cursor to move */
	     SLtt_goto_rc (i, 0);
	     if (Cls_Flag == 0) SLtt_del_eol ();
	     trashed = 1;
	  }
	else trashed = 0;

	if (Cls_Flag || trashed)
	  {
	     int color = This_Color;
	     This_Color = 0;
	     blank_line (SL_Screen[i].old, Screen_Cols, ' ');
	     This_Color = color;
	  }

	SL_Screen[i].old[Screen_Cols] = 0;
	SL_Screen[i].neew[Screen_Cols] = 0;

	SLtt_smart_puts (SL_Screen[i].neew, SL_Screen[i].old, Screen_Cols, i);

	SLMEMCPY ((char *) SL_Screen[i].old, (char *) SL_Screen[i].neew,
		  Screen_Cols * sizeof (short));

	SL_Screen[i].flags = 0;
#ifndef pc_system
	SL_Screen[i].old_hash = SL_Screen[i].new_hash;
#endif
     }

   if (point_visible (1)) SLtt_goto_rc (This_Row - Start_Row, This_Col - Start_Col);
   SLtt_flush_output ();
   Cls_Flag = 0;
}

static int compute_clip (int row, int n, int box_start, int box_end,
			 int *rmin, int *rmax)
{
   int row_max;

   if (n < 0) return 0;
   if (row >= box_end) return 0;
   row_max = row + n;
   if (row_max <= box_start) return 0;

   if (row < box_start) row = box_start;
   if (row_max >= box_end) row_max = box_end;
   *rmin = row;
   *rmax = row_max;
   return 1;
}

void SLsmg_touch_lines (int row, int n)
{
   int i;
   int r1, r2;

   if (0 == compute_clip (row, n, Start_Row, Start_Row + Screen_Rows, &r1, &r2))
     return;

   r1 -= Start_Row;
   r2 -= Start_Row;
   for (i = r1; i < r2; i++)
     {
	SL_Screen[i].flags |= TRASHED;
     }
}

#ifndef pc_system
static char Fake_Alt_Char_Pairs [] = "a:j+k+l+m+q-t+u+v+w+x|";

static void init_alt_char_set (void)
{
   int i;
   unsigned char *p, *pmax, ch;

   if (Alt_Char_Set[128] == 128) return;

   i = 32;
   memset ((char *)Alt_Char_Set, ' ', i);
   while (i <= 128)
     {
	Alt_Char_Set [i] = i;
	i++;
     }

   /* Map to VT100 */
   if (SLtt_Has_Alt_Charset)
     {
	p = (unsigned char *) SLtt_Graphics_Char_Pairs;
	if (p == NULL) return;
     }
   else	p = (unsigned char *) Fake_Alt_Char_Pairs;
   pmax = p + strlen ((char *) p);

   /* Some systems have messed up entries for this */
   while (p < pmax)
     {
	ch = *p++;
	ch &= 0x7F;		       /* should be unnecessary */
	Alt_Char_Set [ch] = *p;
	p++;
     }
}
#endif

#ifndef pc_system
# define BLOCK_SIGNALS SLsig_block_signals ();
# define UNBLOCK_SIGNALS SLsig_unblock_signals ();
#else
# define BLOCK_SIGNALS
# define UNBLOCK_SIGNALS
#endif

static int Smg_Suspended;
void SLsmg_suspend_smg (void)
{
   BLOCK_SIGNALS

   if (Smg_Suspended == 0)
     {
	SLtt_reset_video ();
	Smg_Suspended = 1;
     }

   UNBLOCK_SIGNALS
}

void SLsmg_resume_smg (void)
{
   int i;
   BLOCK_SIGNALS

   if (Smg_Suspended == 0)
     {
	UNBLOCK_SIGNALS
	return;
     }

   Smg_Suspended = 0;
   SLtt_init_video ();
   Cls_Flag = 1;
   for (i = 0; i < Screen_Rows; i++)
     SL_Screen[i].flags |= TRASHED;
   SLsmg_refresh ();

   UNBLOCK_SIGNALS
}

int SLsmg_init_smg (void)
{
   int i, len;
   unsigned short *old, *neew;
   BLOCK_SIGNALS

   if (Smg_Inited) SLsmg_reset_smg ();
   SLtt_init_video ();
   Screen_Cols = SLtt_Screen_Cols;
   Screen_Rows = SLtt_Screen_Rows;
   This_Col = This_Row = Start_Col = Start_Row = 0;

   This_Color = 0;
   This_Alt_Char = 0;
   Cls_Flag = 1;
#ifndef pc_system
   init_alt_char_set ();
#endif
   len = Screen_Cols + 3;
   for (i = 0; i < Screen_Rows; i++)
     {
	if ((NULL == (old = (unsigned short *) SLMALLOC (sizeof(short) * len)))
	    || ((NULL == (neew = (unsigned short *) SLMALLOC (sizeof(short) * len)))))
	  {
	     SLang_Error = SL_MALLOC_ERROR;
	     UNBLOCK_SIGNALS
	     return 0;
	  }
	blank_line (old, len, ' ');
	blank_line (neew, len, ' ');
	SL_Screen[i].old = old;
	SL_Screen[i].neew = neew;
	SL_Screen[i].flags = 0;
#ifndef pc_system
	Blank_Hash = compute_hash (old, Screen_Cols);
	SL_Screen[i].new_hash = SL_Screen[i].old_hash =  Blank_Hash;
#endif
     }
   Smg_Inited = 1;
   UNBLOCK_SIGNALS
   return 1;
}


void SLsmg_reset_smg (void)
{
   int i;
   BLOCK_SIGNALS

   if (Smg_Inited == 0)
     {
	UNBLOCK_SIGNALS
	return;
     }
   for (i = 0; i < Screen_Rows; i++)
     {
	if (SL_Screen[i].old != NULL) SLFREE (SL_Screen[i].old);
	if (SL_Screen[i].neew != NULL) SLFREE (SL_Screen[i].neew);
	SL_Screen[i].old = SL_Screen[i].neew = NULL;
     }
   SLtt_reset_video ();
   This_Alt_Char = This_Color = 0;
   Smg_Inited = 0;

   UNBLOCK_SIGNALS
}


unsigned short SLsmg_char_at (void)
{
   if (point_visible (1))
     {
	return SL_Screen[This_Row - Start_Row].neew[This_Col - Start_Col];
     }
   return 0;
}


void SLsmg_vprintf (char *fmt, va_list ap)
{
   char p[1000];

   (void) vsprintf(p, fmt, ap);

   SLsmg_write_string (p);
}

void SLsmg_set_screen_start (int *r, int *c)
{
   int or = Start_Row, oc = Start_Col;

   if (c == NULL) Start_Col = 0;
   else
     {
	Start_Col = *c;
	*c = oc;
     }
   if (r == NULL) Start_Row = 0;
   else
     {
	Start_Row = *r;
	*r = or;
     }
}

void SLsmg_draw_object (int r, int c, unsigned char object)
{
   This_Row = r;  This_Col = c;

   if (point_visible (1))
     {
	int color = This_Color;
	This_Color |= ALT_CHAR_FLAG;
	SLsmg_write_char (object);
	This_Color = color;
     }

   This_Col = c + 1;
}

void SLsmg_draw_hline (int n)
{
   static unsigned char hbuf[16];
   int count;
   int cmin, cmax;
   int final_col = This_Col + n;
   int save_color;

   if ((This_Row < Start_Row) || (This_Row >= Start_Row + Screen_Rows)
       || (0 == compute_clip (This_Col, n, Start_Col, Start_Col + Screen_Cols,
			      &cmin, &cmax)))
     {
	This_Col = final_col;
	return;
     }

   if (hbuf[0] == 0)
     {
	SLMEMSET ((char *) hbuf, SLSMG_HLINE_CHAR, 16);
     }

   n = cmax - cmin;
   count = n / 16;

   save_color = This_Color;
   This_Color |= ALT_CHAR_FLAG;
   This_Col = cmin;

   SLsmg_write_nchars ((char *) hbuf, n % 16);
   while (count-- > 0)
     {
	SLsmg_write_nchars ((char *) hbuf, 16);
     }

   This_Color = save_color;
   This_Col = final_col;
}

void SLsmg_draw_vline (int n)
{
   unsigned char ch = SLSMG_VLINE_CHAR;
   int c = This_Col, rmin, rmax;
   int final_row = This_Row + n;
   int save_color;

   if (((c < Start_Col) || (c >= Start_Col + Screen_Cols)) ||
       (0 == compute_clip (This_Row, n, Start_Row, Start_Row + Screen_Rows,
			  &rmin, &rmax)))
     {
	This_Row = final_row;
	return;
     }

   save_color = This_Color;
   This_Color |= ALT_CHAR_FLAG;

   for (This_Row = rmin; This_Row < rmax; This_Row++)
     {
	This_Col = c;
	SLsmg_write_nchars ((char *) &ch, 1);
     }

   This_Col = c;  This_Row = final_row;
   This_Color = save_color;
}

void SLsmg_draw_box (int r, int c, int dr, int dc)
{
   if (!dr || !dc) return;
   This_Row = r;  This_Col = c;
   dr--; dc--;
   SLsmg_draw_hline (dc);
   SLsmg_draw_vline (dr);
   This_Row = r;  This_Col = c;
   SLsmg_draw_vline (dr);
   SLsmg_draw_hline (dc);
   SLsmg_draw_object (r, c, SLSMG_ULCORN_CHAR);
   SLsmg_draw_object (r, c + dc, SLSMG_URCORN_CHAR);
   SLsmg_draw_object (r + dr, c, SLSMG_LLCORN_CHAR);
   SLsmg_draw_object (r + dr, c + dc, SLSMG_LRCORN_CHAR);
   This_Row = r; This_Col = c;
}

void SLsmg_fill_region (int r, int c, int dr, int dc, unsigned char ch)
{
   static unsigned char hbuf[16];
   int count;
   int dcmax, rmax;


   if ((dc < 0) || (dr < 0)) return;

   SLsmg_gotorc (r, c);
   r = This_Row; c = This_Col;

   dcmax = Screen_Cols - This_Col;
   if (dc > dcmax) dc = dcmax;

   rmax = This_Row + dr;
   if (rmax > Screen_Rows) rmax = Screen_Rows;

#if 0
   ch = Alt_Char_Set[ch];
#endif
   if (ch != hbuf[0]) SLMEMSET ((char *) hbuf, (char) ch, 16);

   for (This_Row = r; This_Row < rmax; This_Row++)
     {
	This_Col = c;
	count = dc / 16;
	SLsmg_write_nchars ((char *) hbuf, dc % 16);
	while (count-- > 0)
	  {
	     SLsmg_write_nchars ((char *) hbuf, 16);
	  }
     }

   This_Row = r;
}

void SLsmg_forward (int n)
{
   This_Col += n;
}

void SLsmg_write_color_chars (unsigned short *s, unsigned int len)
{
   unsigned short *smax, sh;
   char buf[32], *b, *bmax;
   int color, save_color;

   smax = s + len;
   b = buf;
   bmax = b + sizeof (buf);

   save_color = This_Color;

   while (s < smax)
     {
	sh = *s++;

	color = sh >> 8;
	if ((color != This_Color) || (b == bmax))
	  {
	     if (b != buf)
	       {
		  SLsmg_write_nchars (buf, (int) (b - buf));
		  b = buf;
	       }
	     This_Color = color;
	  }
	*b++ = (char) (sh & 0xFF);
     }

   if (b != buf)
     SLsmg_write_nchars (buf, (int) (b - buf));

   This_Color = save_color;
}

unsigned int SLsmg_read_raw (unsigned short *buf, unsigned int len)
{
   unsigned int r, c;

   if (0 == point_visible (1)) return 0;

   r = (unsigned int) (This_Row - Start_Row);
   c = (unsigned int) (This_Col - Start_Col);

   if (c + len > (unsigned int) Screen_Cols)
     len = (unsigned int) Screen_Cols - c;

   memcpy ((char *) buf, (char *) (SL_Screen[r].neew + c), len * sizeof (short));
   return len;
}

unsigned int SLsmg_write_raw (unsigned short *buf, unsigned int len)
{
   unsigned int r, c;
   unsigned short *dest;

   if (0 == point_visible (1)) return 0;

   r = (unsigned int) (This_Row - Start_Row);
   c = (unsigned int) (This_Col - Start_Col);

   if (c + len > (unsigned int) Screen_Cols)
     len = (unsigned int) Screen_Cols - c;

   dest = SL_Screen[r].neew + c;

   if (0 != memcmp ((char *) dest, (char *) buf, len * sizeof (short)))
     {
	memcpy ((char *) dest, (char *) buf, len * sizeof (short));
	SL_Screen[r].flags |= TOUCHED;
     }
   return len;
}